drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validationgrafted

amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and
uses the first encoding that validates. YCbCr 4:4:4 is listed before
RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the
"color format" property is left at AUTO, even though RGB fits the same
link.

That contradicts the documented AUTO behaviour for HDMI in enum
drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when
the bandwidth is not available or the mode is 4:2:0-only), which the
amdgpu implementation of the property also describes. It also leaves
the "Broadcast RGB" property without effect on such sinks, since the
quantization range it selects only applies to RGB output.

Try RGB first. The mask still holds every encoding the sink supports,
so a mode that cannot carry RGB falls back exactly as before.

For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced
through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI
sink that advertised it.

Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation")
Suggested-by: Adolfo Rodrigues <adolfotregosa@gmail.com>
Assisted-by: Claude Code:claude-fable-5-1
Signed-off-by: Adrian Betschart <adrian.betschart@cinemaone.ch>
Reviewed-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Adolfo Rodrigues <adolfotregosa@gmail.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7)

1 files changed, 341 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-bq32k.c b/drivers/rtc/rtc-bq32k.c
new file mode 100644
index 000000000..573231613
--- /dev/null
+++ b/drivers/rtc/rtc-bq32k.c
@@ -0,0 +1,341 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for TI BQ32000 RTC.
+ *
+ * Copyright (C) 2009 Semihalf.
+ * Copyright (C) 2014 Pavel Machek <pavel@denx.de>
+ *
+ * You can get hardware description at
+ * https://www.ti.com/lit/ds/symlink/bq32000.pdf
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/rtc.h>
+#include <linux/init.h>
+#include <linux/kstrtox.h>
+#include <linux/errno.h>
+#include <linux/bcd.h>
+#include <linux/delay.h>
+
+#define BQ32K_SECONDS		0x00	/* Seconds register address */
+#define BQ32K_SECONDS_MASK	0x7F	/* Mask over seconds value */
+#define BQ32K_STOP		0x80	/* Oscillator Stop flat */
+
+#define BQ32K_MINUTES		0x01	/* Minutes register address */
+#define BQ32K_MINUTES_MASK	0x7F	/* Mask over minutes value */
+#define BQ32K_OF		0x80	/* Oscillator Failure flag */
+
+#define BQ32K_HOURS_MASK	0x3F	/* Mask over hours value */
+#define BQ32K_CENT		0x40	/* Century flag */
+#define BQ32K_CENT_EN		0x80	/* Century flag enable bit */
+
+#define BQ32K_CALIBRATION	0x07	/* CAL_CFG1, calibration and control */
+#define BQ32K_TCH2		0x08	/* Trickle charge enable */
+#define BQ32K_CFG2		0x09	/* Trickle charger control */
+#define BQ32K_TCFE		BIT(6)	/* Trickle charge FET bypass */
+
+#define MAX_LEN			10	/* Maximum number of consecutive
+					 * register for this particular RTC.
+					 */
+
+struct bq32k_regs {
+	uint8_t		seconds;
+	uint8_t		minutes;
+	uint8_t		cent_hours;
+	uint8_t		day;
+	uint8_t		date;
+	uint8_t		month;
+	uint8_t		years;
+};
+
+static struct i2c_driver bq32k_driver;
+
+static int bq32k_read(struct device *dev, void *data, uint8_t off, uint8_t len)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct i2c_msg msgs[] = {
+		{
+			.addr = client->addr,
+			.flags = 0,
+			.len = 1,
+			.buf = &off,
+		}, {
+			.addr = client->addr,
+			.flags = I2C_M_RD,
+			.len = len,
+			.buf = data,
+		}
+	};
+
+	if (i2c_transfer(client->adapter, msgs, 2) == 2)
+		return 0;
+
+	return -EIO;
+}
+
+static int bq32k_write(struct device *dev, void *data, uint8_t off, uint8_t len)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	uint8_t buffer[MAX_LEN + 1];
+
+	buffer[0] = off;
+	memcpy(&buffer[1], data, len);
+
+	if (i2c_master_send(client, buffer, len + 1) == len + 1)
+		return 0;
+
+	return -EIO;
+}
+
+static int bq32k_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct bq32k_regs regs;
+	int error;
+
+	/*
+	 * When the device doesn't have the interrupt connected, prevent
+	 * userpace from polling the RTC registers too frequently.
+	 */
+	if (client->irq <= 0)
+		usleep_range(2000, 2500);
+
+	error = bq32k_read(dev, &regs, 0, sizeof(regs));
+	if (error)
+		return error;
+
+	/*
+	 * In case of oscillator failure, the register contents should be
+	 * considered invalid. The flag is cleared the next time the RTC is set.
+	 */
+	if (regs.minutes & BQ32K_OF)
+		return -EINVAL;
+
+	tm->tm_sec = bcd2bin(regs.seconds & BQ32K_SECONDS_MASK);
+	tm->tm_min = bcd2bin(regs.minutes & BQ32K_MINUTES_MASK);
+	tm->tm_hour = bcd2bin(regs.cent_hours & BQ32K_HOURS_MASK);
+	tm->tm_mday = bcd2bin(regs.date);
+	tm->tm_wday = bcd2bin(regs.day) - 1;
+	tm->tm_mon = bcd2bin(regs.month) - 1;
+	tm->tm_year = bcd2bin(regs.years) +
+				((regs.cent_hours & BQ32K_CENT) ? 100 : 0);
+
+	return 0;
+}
+
+static int bq32k_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct bq32k_regs regs;
+
+	regs.seconds = bin2bcd(tm->tm_sec);
+	regs.minutes = bin2bcd(tm->tm_min);
+	regs.cent_hours = bin2bcd(tm->tm_hour) | BQ32K_CENT_EN;
+	regs.day = bin2bcd(tm->tm_wday + 1);
+	regs.date = bin2bcd(tm->tm_mday);
+	regs.month = bin2bcd(tm->tm_mon + 1);
+
+	if (tm->tm_year >= 100) {
+		regs.cent_hours |= BQ32K_CENT;
+		regs.years = bin2bcd(tm->tm_year - 100);
+	} else
+		regs.years = bin2bcd(tm->tm_year);
+
+	return bq32k_write(dev, &regs, 0, sizeof(regs));
+}
+
+static const struct rtc_class_ops bq32k_rtc_ops = {
+	.read_time	= bq32k_rtc_read_time,
+	.set_time	= bq32k_rtc_set_time,
+};
+
+static int trickle_charger_of_init(struct device *dev, struct device_node *node)
+{
+	unsigned char reg;
+	int error;
+	u32 ohms = 0;
+
+	if (of_property_read_u32(node, "trickle-resistor-ohms" , &ohms))
+		return 0;
+
+	switch (ohms) {
+	case 180+940:
+		/*
+		 * TCHE[3:0] == 0x05, TCH2 == 1, TCFE == 0 (charging
+		 * over diode and 940ohm resistor)
+		 */
+
+		if (of_property_read_bool(node, "trickle-diode-disable")) {
+			dev_err(dev, "diode and resistor mismatch\n");
+			return -EINVAL;
+		}
+		reg = 0x05;
+		break;
+
+	case 180+20000:
+		/* diode disabled */
+
+		if (!of_property_read_bool(node, "trickle-diode-disable")) {
+			dev_err(dev, "bq32k: diode and resistor mismatch\n");
+			return -EINVAL;
+		}
+		reg = 0x45;
+		break;
+
+	default:
+		dev_err(dev, "invalid resistor value (%d)\n", ohms);
+		return -EINVAL;
+	}
+
+	error = bq32k_write(dev, &reg, BQ32K_CFG2, 1);
+	if (error)
+		return error;
+
+	reg = 0x20;
+	error = bq32k_write(dev, &reg, BQ32K_TCH2, 1);
+	if (error)
+		return error;
+
+	dev_info(dev, "Enabled trickle RTC battery charge.\n");
+	return 0;
+}
+
+static ssize_t bq32k_sysfs_show_tricklecharge_bypass(struct device *dev,
+					       struct device_attribute *attr,
+					       char *buf)
+{
+	int reg, error;
+
+	error = bq32k_read(dev, &reg, BQ32K_CFG2, 1);
+	if (error)
+		return error;
+
+	return sprintf(buf, "%d\n", (reg & BQ32K_TCFE) ? 1 : 0);
+}
+
+static ssize_t bq32k_sysfs_store_tricklecharge_bypass(struct device *dev,
+						struct device_attribute *attr,
+						const char *buf, size_t count)
+{
+	int reg, enable, error;
+
+	if (kstrtoint(buf, 0, &enable))
+		return -EINVAL;
+
+	error = bq32k_read(dev, &reg, BQ32K_CFG2, 1);
+	if (error)
+		return error;
+
+	if (enable) {
+		reg |= BQ32K_TCFE;
+		error = bq32k_write(dev, &reg, BQ32K_CFG2, 1);
+		if (error)
+			return error;
+
+		dev_info(dev, "Enabled trickle charge FET bypass.\n");
+	} else {
+		reg &= ~BQ32K_TCFE;
+		error = bq32k_write(dev, &reg, BQ32K_CFG2, 1);
+		if (error)
+			return error;
+
+		dev_info(dev, "Disabled trickle charge FET bypass.\n");
+	}
+
+	return count;
+}
+
+static DEVICE_ATTR(trickle_charge_bypass, 0644,
+		   bq32k_sysfs_show_tricklecharge_bypass,
+		   bq32k_sysfs_store_tricklecharge_bypass);
+
+static int bq32k_sysfs_register(struct device *dev)
+{
+	return device_create_file(dev, &dev_attr_trickle_charge_bypass);
+}
+
+static void bq32k_sysfs_unregister(struct device *dev)
+{
+	device_remove_file(dev, &dev_attr_trickle_charge_bypass);
+}
+
+static int bq32k_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct rtc_device *rtc;
+	uint8_t reg;
+	int error;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -ENODEV;
+
+	/* Check Oscillator Stop flag */
+	error = bq32k_read(dev, &reg, BQ32K_SECONDS, 1);
+	if (!error && (reg & BQ32K_STOP)) {
+		dev_warn(dev, "Oscillator was halted. Restarting...\n");
+		reg &= ~BQ32K_STOP;
+		error = bq32k_write(dev, &reg, BQ32K_SECONDS, 1);
+	}
+	if (error)
+		return error;
+
+	/* Check Oscillator Failure flag */
+	error = bq32k_read(dev, &reg, BQ32K_MINUTES, 1);
+	if (error)
+		return error;
+	if (reg & BQ32K_OF)
+		dev_warn(dev, "Oscillator Failure. Check RTC battery.\n");
+
+	if (client->dev.of_node)
+		trickle_charger_of_init(dev, client->dev.of_node);
+
+	rtc = devm_rtc_device_register(&client->dev, bq32k_driver.driver.name,
+						&bq32k_rtc_ops, THIS_MODULE);
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
+
+	error = bq32k_sysfs_register(&client->dev);
+	if (error) {
+		dev_err(&client->dev,
+			"Unable to create sysfs entries for rtc bq32000\n");
+		return error;
+	}
+
+
+	i2c_set_clientdata(client, rtc);
+
+	return 0;
+}
+
+static void bq32k_remove(struct i2c_client *client)
+{
+	bq32k_sysfs_unregister(&client->dev);
+}
+
+static const struct i2c_device_id bq32k_id[] = {
+	{ .name = "bq32000" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, bq32k_id);
+
+static const __maybe_unused struct of_device_id bq32k_of_match[] = {
+	{ .compatible = "ti,bq32000" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, bq32k_of_match);
+
+static struct i2c_driver bq32k_driver = {
+	.driver = {
+		.name	= "bq32k",
+		.of_match_table = of_match_ptr(bq32k_of_match),
+	},
+	.probe		= bq32k_probe,
+	.remove		= bq32k_remove,
+	.id_table	= bq32k_id,
+};
+
+module_i2c_driver(bq32k_driver);
+
+MODULE_AUTHOR("Semihalf, Piotr Ziecik <kosmo@semihalf.com>");
+MODULE_DESCRIPTION("TI BQ32000 I2C RTC driver");
+MODULE_LICENSE("GPL");